Oilseed rape (Brassica napus): the importance of aminopeptidases in germination under normal and heavy metals stress conditions

Abstract

BACKGROUND: Oilseed rape is one of the most important oilseed crops worldwide, crucial in the food and feed industries. Different environment and climatic conditions can influence its sustainable cultivation and crop yield. Aminopeptidases are crucial enzymes in many physiological processes in all organisms, including humans, so it is important to learn their behavior in food and feed sources. This study presents, for the first time, a detailed discussion on the importance of aminopeptidases, during the oilseed rape germination process, under standard and stress conditions. RESULTS: During the germination of oilseed rape under standard conditions, a significant increase in aminopeptidases activity toward N-terminal amino acidsphenylalanine (Phe), alanine (Ala), glycine (Gly), leucine (Leu), proline (Pro), methionine (Met) was observed. The change was substrate specific, with the highest increase being observed for Gly (3.2-fold), followed by Ala (2.9-fold), Pro (2.5-fold), Met (1.5-fold), and Phe (1.3-fold). Generally, N-terminal Phe was preferentially cleaved. Germination under stress conditions, caused by several heavy metal ions (e.g. divalent copper, zinc, cadmium, and lead ions), negatively influenced the plants' growth and quality, but significantly enhanced the expression of genes encoding aminopeptidases (or potentially activated aminopeptidases precursors), which was related to the dramatic increase of their activity.CONCLUSIONS: The activity/concentration of aminopeptidases in plants is adjusted to the needs at each stage of development and stress factors occurrence. The most significant increase of activity toward N-terminal Gly and Pro proved the key role of aminopeptidases in the defense mechanisms, by supplying the plants with osmoprotectants and organic nitrogen. The results provide new concepts of oilseed rape growth and cultivation under different conditions.

Promising New Methods Based on the SOD Enzyme and SAUR36 Gene to Screen for Canola Materials with Heavy Metal Resistance

“…The experimental design is 16 h a day of illumination, 8 h of darkness, a temperature of 25 °C, and an illumination intensity of 2455 lux. The experimental method referred to Soares et al [ 30 ] and Kania et al [ 31 ].…”

“…The experimental design is 16 h a day of illumination, 8 h of darkness, a temperature of 25 • C, and an illumination intensity of 2455 lux. The experimental method referred to Soares et al [30] and Kania et al [31]. For indoor experimental materials, we mainly recorded germination potential, germination rate, emergence rate, and biomass of seeds on the seventh day after germination.…”

Characterization of leucine aminopeptidase (LAP) activity in sweet pepper fruits during ripening and its inhibition by nitration and reducing events

“…They play an essential role in cell protein turnover but also in physiological processes such as defense mechanisms against biotic and abiotic stresses (Matsui et al 2006 ; Waditee-Sirisattha et al 2011 ). In higher plants, research on APs has been focused on processes such as seed germination or in response to different stresses (Jaouani et al 2018 ; Kania et al 2021 ). APs also participate in the redistribution of amino acids from storing sink tissues during germination, although little is known about the role of AP in this process (Chao et al 1999 ), as well as on their subcellular localization (Corpas et al 1993 ; Narváez-Vásquez et al 2008 ).…”

Identification and functional analysis of cation-efflux transporter 1 from Brassica juncea L.

“…Many Brassicaceae plants have particular mechanisms for heavy metal ion detoxification and homeostasis [ 6 – 8 ]. Several cation transporter families are involved in metal transport and storage, such as cation diffusion facilitator (CDF) proteins, natural resistance-associated macrophage proteins, yellow-stripe 1-like proteins, zinc-regulated transporter and iron-related transporter proteins, and cation exchangers [ 9 , 10 ].…”